Real-Time Signal Control Method for Multi-Approach Roundabouts

A real-time traffic signal optimization model with the objective of minimizing the stagnant vehicles in the circulatory lanes and queuing vehicles on entries is proposed. According to real-time data collected by sensors, the optimization model activates changes of traffic signal cycle time and signal timing. The arrangement of sensors takes into consideration of departure traffic flow and vehicle queue on entries respectively, by which record and prediction of real-time traffic condition is more accurate. A MATLAB simulation of demonstrating the effectiveness of the optimization model is also presented.